This shrinks "struct object" by a small amount, by getting rid of the
"struct type *" pointer and replacing it with a 3-bit bitfield instead.
In addition, we merge the bitfields and the "flags" field, which
incidentally should also remove a useless 4-byte padding from the object
when in 64-bit mode.
Now, our "struct object" is still too damn large, but it's now less
obviously bloated, and of the remaining fields, only the "util" (which is
not used by most things) is clearly something that should be eventually
discarded.
This shrinks the "git-rev-list --all" memory use by about 2.5% on the
kernel archive (and, perhaps more importantly, on the larger mozilla
archive). That may not sound like much, but I suspect it's more on a
64-bit platform.
There are other remaining inefficiencies (the parent lists, for example,
probably have horrible malloc overhead), but this was pretty obvious.
Most of the patch is just changing the comparison of the "type" pointer
from one of the constant string pointers to the appropriate new TYPE_xxx
small integer constant.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
The minimum length of abbreviated object name was hardcoded in
different places to be 4, risking inconsistencies in the future.
Also there were three different "default abbreviation
precision". Use two C preprocessor symbols to clean up this
mess.
Signed-off-by: Junio C Hamano <junkio@cox.net>
When describing more than one, we need to clear the commit marks
before handling the next one, but most of the time we are
running it for only one commit, and in such a case this clearing
phase is totally unnecessary.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This is based on the patch by Andreas Ericsson, but done slightly
differently, preferring to have separate loops -- one for options
and then arguments.
Signed-off-by: Junio C Hamano <junkio@cox.net>
The main loop was prepared to take more than one revs, but the actual
naming logic wad not (it used pop_most_recent_commit while forgetting
that the commit marks stay after it's done).
Signed-off-by: Junio C Hamano <junkio@cox.net>
Even though --all and --tags can be used to include non
annotated tags in the reference point candidates, prefer to use
annotated tags if there are more than one refs that name the
same commit.
Signed-off-by: Junio C Hamano <junkio@cox.net>
With --tags, not just annontated tags, but also any ref under
refs/tags/ are used to name the revision.
The number of digits is configurable with the --abbrev=<n> option.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Often there are references other than annotated tags under
refs/tags hierarchy that are used to "keep things just in case".
default to use annotated tags only, still leaving the option to
use any ref with --all flag.
Signed-off-by: Junio C Hamano <junkio@cox.net>
It shows you the most recent tag that is reachable from a particular
commit is.
Maybe this is something that "git-name-rev" should be taught to do,
instead of having a separate command for it. Regardless, I find it useful.
What it does is to take any random commit, and "name" it by looking up the
most recent commit that is tagged and reachable from that commit. If the
match is exact, it will just print out that ref-name directly. Otherwise
it will print out the ref-name, followed by the 8-character "short SHA".
IOW, with something like Junios current tree, I get:
[torvalds@g5 git]$ git-describe parent
refs/tags/v1.0.4-g2414721b
ie the current head of my "parent" branch (ie Junio) is based on v1.0.4,
but since it has a few commits on top of that, it has added the git hash
of the thing to the end: "-g" + 8-char shorthand for the commit
2414721b19.
Doing a "git-describe" on a tag-name will just show the full tag path:
[torvalds@g5 git]$ git-describe v1.0.4
refs/tags/v1.0.4
unless there are _other_ tags pointing to that commit, in which case it
will just choose one at random.
This is useful for two things:
- automatic version naming in Makefiles, for example. We could use it in
git itself: when doing "git --version", we could use this to give a
much more useful description of exactly what version was installed.
- for any random commit (say, you use "gitk <pathname>" or
"git-whatchanged" to look at what has changed in some file), you can
figure out what the last version of the repo was. Ie, say I find a bug
in commit 39ca371c45b04cd50d0974030ae051906fc516b6, I just do:
[torvalds@g5 linux]$ git-describe 39ca371c45b04cd50d0974030ae051906fc516b6
refs/tags/v2.6.14-rc4-g39ca371c
and I now know that it was _not_ in v2.6.14-rc4, but was presumably in
v2.6.14-rc5.
The latter is useful when you want to see what "version timeframe" a
commit happened in.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
